What does the file look like in a hex editor?
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Jon SkeetAug 21 '09 at 11:23

It looks fine, no bunches of 7f and 80's :)
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EzombortAug 21 '09 at 11:32

The question may sound stupid, but as the file looks fine in the hex editor and not from .NET, are you definitely certain that you are opening the same file?
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Dirk Vollmar - 0xA3Aug 21 '09 at 11:57

Well, other than overusing the var keyword and not closing the file after reading it, I don't see anything wrong with the code. How did you determine that there are 127s and 128s in the array, and what is your code for playing the sound?
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GuffaAug 21 '09 at 11:58

This was not the problem after all, so I'll have to continue my search for the real bug. Thanks for helping and sorry.
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EzombortAug 21 '09 at 12:14